Abstract

When choosing a mate, humans favour genetic traits (attractiveness, high sex drive) for short-term relationships and parental traits (warmth, high status) for long-term relationships. These preferences serve to maximise fitness of future offspring. But this model neglects the role of social norms in shaping evolved mating strategies. For example, in conservative cultures, individuals are likely to face costs such as punishment for short-term mating. Here we show that conservatives over-perceive some mates' suitability as long-term partners. Study 1 found that conservatives were less likely to use a short-term strategy that was distinctive from their long-term strategy. Study 2 showed that conservatives over-perceived hypothetical mates as long-term investing partners, despite their lack of commitment-compatible traits. Conservatism was measured at the regional- (India, USA, UK) and individual-level. Our results demonstrate how social norms may bias behaviour. We anticipate our findings to be a starting point for more sophisticated models, drawing on developments from evolutionary and social psychology.